A paperboard printing deviation correction device based on machine vision

Abstract

The application relates to the technical field of paperboard processing devices, in particular to a paperboard printing deviation precision correction device based on machine vision, which comprises a rack and a working assembly, the working assembly comprises two rollers, two conveying motors, a conveying belt, multiple correction components and a controller; the correction component comprises a driving part, two pushing parts, a support and a visual camera; the paperboard to be printed is placed on the conveying belt for transportation, the visual camera carries out visual detection on the paperboard on the conveying belt, the offset of the paperboard is calculated through an image algorithm, and an offset signal is transmitted to the controller; when the paperboard is detected to deviate on the conveying belt, the controller controls the conveying motor to stop, simultaneously controls the driving part under the same correction component as the visual camera to drive the two pushing parts to move close to each other, and the two pushing parts push the paperboard to move to the middle of the conveying belt, so that the paperboard deviating on the conveying belt can be precisely corrected.

Description

Technical Field

[0001] This invention relates to the field of paperboard processing equipment technology, and in particular to a machine vision-based device for precise correction of misalignment in paperboard printing. Background Technology

[0002] During the cardboard printing process, the cardboard is easily misaligned or tilted at high speeds on the conveyor belt due to various factors such as conveyor belt vibration, cardboard dimensional tolerances, feeding position deviations, and environmental factors. Cardboard misalignment not only leads to subsequent printing pattern misalignment and misregistration, affecting the overall quality of the printed product, but can also cause positioning failures in later processes such as die-cutting and box gluing, increasing scrap rates and severely restricting production efficiency and yield improvement. Therefore, accurately detecting and promptly correcting positional deviations during cardboard conveying has become a critical technical problem that the printing and packaging industry urgently needs to solve.

[0003] Existing measures to address cardboard deviation mainly rely on mechanical limiting correction. This involves installing fixed baffles on both sides of the conveyor belt, which limit the deviation range by the collision or friction between the cardboard and the baffles. This method is essentially a passive blocking rather than an active correction. When the deviation is small, the baffles cannot contact the cardboard, and the deviation still exists. When the deviation is large, the edges of the cardboard collide violently with the baffles, which not only fails to push the cardboard back to the center position but may also cause the cardboard to fold or get stuck.

[0004] For the reasons mentioned above, there is an urgent need for a device that can accurately correct cardboard that is misaligned on the conveyor belt during the cardboard printing process. Summary of the Invention

[0005] The purpose of this invention is to provide a machine vision-based device for accurately correcting misalignment in cardboard printing, which can accurately correct misaligned cardboard being transported on a conveyor belt.

[0006] To achieve the above objectives, the present invention provides a machine vision-based device for precise correction of misalignment in cardboard printing, comprising a frame and a working assembly, wherein the working assembly includes two rollers, two conveyor motors, a conveyor belt, multiple correction components, and a controller. Two rollers are rotatably connected to the frame and located on opposite sides of the frame. Two conveyor motors are fixedly connected to the frame, and their output ends are fixedly connected to the two rollers and located on opposite sides of the frame. A conveyor belt is fitted over the outside of the two rollers. Multiple correction components are located on the top of the frame, each including a drive unit, two push units, a bracket, and a vision camera. The drive unit is located on the top of the frame. The two push units are located on opposite sides of the drive unit. The bracket is located on the side of the drive unit. The vision camera is fixedly connected to the bracket and located at the bottom of the bracket. The controller is fixedly connected to the side of the frame and electrically connected to the two conveyor motors and the vision camera.

[0007] The drive unit includes two columns, a guide rail, a bidirectional threaded screw, two threaded nuts, and a drive motor. The two columns are fixedly connected to the frame and located on both sides of the frame. The guide rail is fixedly connected to the top of the two columns. The bidirectional threaded screw is rotatably connected to the guide rail and located inside the guide rail. The two threaded nuts are slidably connected to the guide rail and threadedly connected to the bidirectional threaded screw, and located inside the guide rail. The drive motor is fixedly connected to the guide rail, and the output end of the drive motor is fixedly connected to the bidirectional threaded screw and located on the side of the guide rail. The drive motor is electrically connected to the controller.

[0008] The pushing part includes a sliding arm and a push plate; the sliding arm is fixedly connected to the nut seat and is located on the side of the nut seat; the push plate is fixedly connected to the sliding arm and is located on the side of the sliding arm.

[0009] The pushing part further includes two pulleys; the two pulleys are rotatably connected to the column and are located inside the column and on both sides of the sliding arm.

[0010] The pushing part further includes an anti-wear pad; the anti-wear pad is fixedly connected to the push plate and is located on the side of the push plate.

[0011] The machine vision-based cardboard printing deviation correction device also includes two limiting components; the two limiting components are respectively disposed at the bottom of the guide rail.

[0012] The limiting component includes a lifting component and a rolling component; the lifting component is disposed at the bottom of the guide rail; and the rolling component is disposed at the bottom of the lifting component.

[0013] This invention discloses a machine vision-based device for precisely correcting misalignment in cardboard printing. The cardboard to be printed is placed on a conveyor belt. A conveyor motor drives a roller to rotate, which in turn moves the conveyor belt, transporting the cardboard. A vision camera visually detects the cardboard on the conveyor belt, calculates the cardboard's offset using an image algorithm, and transmits the offset signal to a controller. When misalignment is detected, the controller stops the conveyor motor and simultaneously controls a drive unit located under the same correction component as the vision camera to move two pushing units closer together. These two pushing units push the cardboard towards the center of the conveyor belt, correcting its position. Once the vision camera detects that the cardboard is centered, the controller restarts the conveyor motor to continue transporting the cardboard. This method enables precise correction of misaligned cardboard on the conveyor belt. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below.

[0015] Figure 1 This is a schematic diagram of the overall structure of the first embodiment of the present invention.

[0016] Figure 2 This is a front cross-sectional view of the entire first embodiment of the present invention.

[0017] Figure 3 This is a side sectional view of the entire first embodiment of the present invention.

[0018] Figure 4 This is a schematic diagram of the overall structure of the second embodiment of the present invention.

[0019] Figure 5 This is a schematic diagram of the limiting component according to the second embodiment of the present invention.

[0020] Figure 6 This is a side cross-sectional view of the limiting component according to the second embodiment of the present invention.

[0021] 101-Frame, 102-Roller, 103-Conveyor Motor, 104-Conveyor Belt, 105-Correcting Component, 106-Controller, 107-Drive Unit, 108-Push Unit, 109-Bracket, 110-Vision Camera, 111-Column, 112-Guide Rail, 113-Double-Directional Screw, 114-Screw Nut, 115-Drive Motor, 116-Sliding Arm, 117-Push Plate, 118-Pulley, 119-Anti-wear Pad, 201-Limiting Component, 202-Lifting Component, 203-Rolling Component, 204-Cylinder, 205-Connecting Rod, 206-Mounting Base, 207-Ball Ball. Detailed Implementation

[0022] The embodiments of the present invention are described in detail below. Examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, but should not be construed as limiting the present invention.

[0023] The first embodiment of this application is as follows: Please see Figures 1-3 ,in, Figure 1 This is a schematic diagram of the overall structure of the first embodiment of the present invention; Figure 2 This is a front sectional view of the entire first embodiment of the present invention; Figure 3 This is a side sectional view of the entire first embodiment of the present invention.

[0024] This invention provides a machine vision-based device for accurately correcting misalignment in cardboard printing, comprising a frame 101 and a working assembly. The working assembly includes two rollers 102, two conveyor motors 103, a conveyor belt 104, multiple correction components 105, and a controller 106. Each correction component 105 includes a drive unit 107, two push units 108, a support 109, and a vision camera 110. The drive unit 107 includes two columns 111, a guide rail 112, a bidirectional threaded screw 113, two thread nuts 114, and a drive motor 115. Each push unit 108 includes a sliding arm 116, a push plate 117, two pulleys 118, and an anti-wear pad 119. This device enables accurate correction of misaligned cardboard being conveyed on the conveyor belt 104.

[0025] In this specific embodiment, the two rollers 102 are rotatably connected to the frame 101 and are located on opposite sides of the frame 101; the two conveyor motors 103 are fixedly connected to the frame 101, and their output ends are fixedly connected to the two rollers 102 and located on opposite sides of the frame 101; the conveyor belt 104 is sleeved on the outside of the two rollers 102; and multiple correction components 105 are located on the top of the frame 101. The system includes a drive unit 107, two push units 108, a bracket 109, and a vision camera 110. The drive unit 107 is located on the top of the frame 101. The two push units 108 are located on both sides of the drive unit 107. The bracket 109 is located on the side of the drive unit 107. The vision camera 110 is fixedly connected to the bracket 109 and is located at the bottom of the bracket 109. The controller 106 is fixedly connected to the side of the frame 101 and is electrically connected to the two conveyor motors 103 and the vision camera 110. The cardboard to be printed is placed on the conveyor belt 104. The conveyor motor 103 drives the roller 102 to rotate, and the roller 102 drives the conveyor belt 104 to move and transport the cardboard. The vision camera 110 performs visual detection on the cardboard on the conveyor belt 104, calculates the offset of the cardboard through an image algorithm, and transmits the offset signal to the controller 106. When the cardboard is detected to be off-track on the conveyor belt 104, the controller 106 controls the conveyor motor 103 to stop. At the same time, it controls the drive unit 107, which is located under the same correction component 105 as the vision camera 110, to drive the two push units 108 to move closer to each other. The two push units 108 push the cardboard to move towards the center of the conveyor belt 104 to correct the position of the cardboard. After the vision camera 110 detects that the cardboard is centered, the controller 106 controls the conveyor motor 103 to start again to continue transporting the cardboard. In this way, the off-track cardboard on the conveyor belt 104 can be accurately corrected.

[0026] The two uprights 111 are fixedly connected to the frame 101 and located on both sides of the frame 101; the guide rail 112 is fixedly connected to the top of the two uprights 111; the bidirectional threaded screw 113 is rotatably connected to the guide rail 112 and located inside the guide rail 112; the two threaded nuts 114 are slidably connected to the guide rail 112 and threadedly connected to the bidirectional threaded screw 113, and located inside the guide rail 112; the drive motor 115 is fixedly connected to the guide rail 112, and the output end of the drive motor 115 is fixedly connected to the bidirectional threaded screw 113 and located on the side of the guide rail 112; the drive motor 115 is electrically connected to the controller 106. The bidirectional threaded screw 113 has external threads with opposite thread directions at both ends. The two threaded nuts 114 are located at the two ends of the bidirectional threaded screw 113 with opposite thread directions. The guide rail 112 provides guidance when the threaded nuts 114 slide and prevents the threaded nuts 114 from deviating. The bidirectional threaded screw 113 can be driven to rotate by the drive motor 115. The rotation of the bidirectional threaded screw 113 causes the two threaded nuts 114 to move towards each other or away from each other. The threaded nuts 114 drive the pusher 108 to move, thereby causing the two pushers 108 to move away from each other or towards each other.

[0027] Secondly, the sliding arm 116 is fixedly connected to the liner seat 114 and is located on the side of the liner seat 114; the push plate 117 is fixedly connected to the sliding arm 116 and is located on the side of the sliding arm 116. The sliding arm 116 is used to connect the push plate 117 and the liner seat 114, and the push plate 117 is used to push the misaligned cardboard.

[0028] Meanwhile, the two pulleys 118 are rotatably connected to the column 111 and are located inside the column 111, on both sides of the sliding arm 116. The column 111 provides guidance for the movement of the sliding arm 116, and the pulleys 118 make the movement of the sliding arm 116 smoother.

[0029] In addition, the anti-abrasion pad 119 is fixedly connected to the push plate 117 and is located on the side of the push plate 117. The anti-abrasion pad 119 contacts the cardboard and pushes the cardboard, which can prevent wear and tear on the cardboard.

[0030] In using this invention, the cardboard to be printed is placed on the conveyor belt 104. The conveyor motor 103 drives the roller 102 to rotate, and the roller 102 drives the conveyor belt 104 to move, transporting the cardboard. The vision camera 110 performs visual inspection on the cardboard on the conveyor belt 104, calculates the offset of the cardboard using an image algorithm, and transmits the offset signal to the controller 106. When the cardboard is detected to be deviating on the conveyor belt 104, the controller 106 controls the conveyor motor 103 to stop, and simultaneously controls the drive motor 115, which is located under the same correction component 105 as the vision camera 110, to drive the bidirectional threaded screw 113 to rotate forward. The rotation of the bidirectional threaded screw 113 causes the two threaded nuts 114 to move closer to each other. The two threaded nuts 114, via the sliding arm 116, drive the two push plates 117 to move closer to each other. The two anti-wear pads 119 push the cardboard towards the center of the conveyor belt 104 to correct the cardboard's position. After the vision camera 110 detects that the cardboard is centered, the controller 106 controls the drive motor 115 to drive the bidirectional threaded screw 113 to reverse. The two push plates 117 move away from the cardboard and reset. Then, the conveyor motor 103 starts to continue conveying the cardboard. In this way, cardboard that has deviated from its designated path on the conveyor belt 104 can be accurately corrected.

[0031] The second embodiment of this application is as follows: Based on the first embodiment, please refer to Figures 4-6 ,in, Figure 4 This is a schematic diagram of the overall structure of the second embodiment of the present invention; Figure 5 This is a schematic diagram of the limiting component according to the second embodiment of the present invention; Figure 6 This is a side cross-sectional view of the limiting component according to the second embodiment of the present invention.

[0032] The present invention provides a machine vision-based cardboard printing deviation correction device, which further includes two limiting components 201. The limiting components 201 include a lifting component 202 and a rolling component 203. The lifting component 202 includes a cylinder 204 and a connecting rod 205. The rolling component 203 includes a mounting base 206 and a ball bearing 207.

[0033] In this specific embodiment, the two limiting components 201 are respectively disposed at the bottom of the guide rail 112. The limiting components 201 can limit the cardboard on the conveyor belt 104 from top to bottom, preventing the cardboard from jumping on the conveyor belt 104, thereby preventing the cardboard from deviating due to jumping.

[0034] The lifting component 202 is located at the bottom of the guide rail 112; the rolling component 203 is located at the bottom of the lifting component 202. The rolling component 203 is used to limit the cardboard on the conveyor belt 104 from top to bottom, preventing the cardboard from jumping on the conveyor belt 104, thereby preventing the cardboard from deviating due to jumping. The rolling component 203 can roll on the cardboard, thereby reducing the friction between the cardboard and the cardboard when the cardboard moves. The lifting component 202 is used to adjust the height of the rolling component 203 to accommodate cardboard of different thicknesses.

[0035] Secondly, the cylinder 204 is fixedly connected to the guide rail 112 and is located at the bottom of the guide rail 112; the connecting rod 205 is fixedly connected to the output rod of the cylinder 204 and is located at the bottom of the cylinder 204. The cylinder 204 can drive the connecting rod 205 and the rolling component 203 to move longitudinally to accommodate cardboard of different thicknesses.

[0036] Furthermore, the mounting base 206 is fixedly connected to the connecting rod 205 and is located at the bottom of the connecting rod 205; the ball bearing 207 is located inside the mounting base 206. The mounting base 206 confines the ball bearing 207 internally, with one-third of the ball bearing 207 extending out of the mounting base 206. The ball bearing 207 limits the movement of the cardboard on the conveyor belt 104 from top to bottom. By rolling, the friction between the ball bearing and the cardboard is reduced as the cardboard moves.

[0037] When using this invention, the ball bearing 207 is used to limit the cardboard on the conveyor belt 104 from top to bottom, preventing the cardboard from jumping on the conveyor belt 104, thereby preventing the cardboard from deviating due to jumping. The ball bearing 207 can roll on the cardboard, thereby reducing the friction between the cardboard and the cardboard when the cardboard moves. The cylinder 204 and the connecting rod 205 are used to adjust the height of the mounting base 206 and the ball bearing 207 to accommodate cardboard of different thicknesses.

[0038] The above-disclosed embodiments are merely one or more preferred embodiments of this application and should not be construed as limiting the scope of this application. Those skilled in the art can understand that all or part of the processes for implementing the above embodiments and equivalent changes made in accordance with the claims of this application still fall within the scope of this application.

Claims

1. A machine vision-based device for precise correction of misalignment in cardboard printing, comprising a frame, characterized in that, It also includes working components; The working assembly includes two rollers, two conveyor motors, a conveyor belt, multiple correction components, and a controller; Two rollers are rotatably connected to the frame and are located on opposite sides of the frame. Two conveyor motors are fixedly connected to the frame, and their output ends are fixedly connected to the rollers and located on opposite sides of the frame. A conveyor belt is fitted over the outside of the rollers. Multiple correction components are located on the top of the frame, each including a drive unit, two push units, a bracket, and a vision camera. The drive unit is located on the top of the frame. The two push units are located on opposite sides of the drive unit. The bracket is located on the side of the drive unit. The vision camera is fixedly connected to the bracket and located at the bottom of the bracket. The controller is fixedly connected to the side of the frame and electrically connected to the two conveyor motors and the vision camera.

2. The machine vision-based cardboard printing deviation correction device as described in claim 1, characterized in that, The drive unit includes two columns, a guide rail, a bidirectional threaded screw, two threaded nuts, and a drive motor. The two columns are fixedly connected to the frame and located on both sides of the frame. The guide rail is fixedly connected to the top of the two columns. The bidirectional threaded screw is rotatably connected to the guide rail and located inside the guide rail. The two threaded nuts are slidably connected to the guide rail and threadedly connected to the bidirectional threaded screw, and located inside the guide rail. The drive motor is fixedly connected to the guide rail, and the output end of the drive motor is fixedly connected to the bidirectional threaded screw and located on the side of the guide rail. The drive motor is electrically connected to the controller.

3. The machine vision-based cardboard printing deviation correction device as described in claim 2, characterized in that, The pushing part includes a sliding arm and a push plate; the sliding arm is fixedly connected to the nut seat and is located on the side of the nut seat; the push plate is fixedly connected to the sliding arm and is located on the side of the sliding arm.

4. The machine vision-based cardboard printing deviation correction device as described in claim 3, characterized in that, The pushing part also includes two pulleys; the two pulleys are rotatably connected to the column and are located inside the column and on both sides of the sliding arm.

5. The machine vision-based cardboard printing deviation correction device as described in claim 4, characterized in that, The pushing part also includes an anti-wear pad; the anti-wear pad is fixedly connected to the push plate and is located on the side of the push plate.

6. The machine vision-based cardboard printing deviation correction device as described in claim 5, characterized in that, The machine vision-based cardboard printing deviation correction device also includes two limiting components; the two limiting components are respectively disposed at the bottom of the guide rail.

7. The machine vision-based cardboard printing misalignment correction device as described in claim 6, characterized in that, The limiting component includes a lifting component and a rolling component; the lifting component is disposed at the bottom of the guide rail; the rolling component is disposed at the bottom of the lifting component.

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